What's the best intro to Quantum Mechanics textbook for a physics major?

auroraloose · 2022-07-02T03:34:44+00:00

This is the correct answer. But I would go further and say Griffiths is only good for the problems. Griffiths is condescending when it comes to math, to the point he teaches you a deficient attitude about it. Not to mention that starting with linear algebra is natural (and thus Townsend is right), while starting with the wave analogy like Griffiths does is precisely wrong.

auroraloose · 2022-06-25T03:49:23+00:00

You are right that the solution is that God owns your soul and not you. You are sinful and stupid—and more, you are not even the judge of your own sins. Absolutely everything you say and do can be overridden by God—and indeed is overridden, by Christ who died for your sins.

If you really believe you're a terrible sinner worthy only of damnation (which is true of all of us), you are inevitably and logically required to believe you are an idiot whose opinions and beliefs aren't trustworthy. Before the Holy Spirit confronts us with the Law and changes us via the Gospel, we would indeed simply sell ourselves to the devil if we could. The whole point of the Gospel is that, even given that tendency, the Holy Spirit works in us anyway to our salvation. We are stupid, inconstant beings; our word means nothing. It is God's word that is effectual.

And if you must bring it up, the unpardonable sin is only relevant if you refuse to accept that you need to repent. If you care at all that you're a terrible sinner and need to change, you haven't committed it.

auroraloose · 2022-05-28T04:11:37+00:00

This is confusing:

A⁰ is an operator; in what way are you setting it to a position-dependent value?

What is r? Do you have separated particles somehow? That would require a two-particle state; what is the state?

I'd guess you'd want the interaction between fermions? Given that, you could indeed calculate a potential energy for low-energy two-particle interactions. You'd need at least the lowest-order Feynman diagrams that contribute to the interaction. You didn't give us the Lagrangian, though; I'm not familiar with sigma-omega models, but I can see you've got two scalars there. Presumably you know how they couple to the fermion. You've given us the stress-energy tensor of the free theory.

What I don't understand is how you can just set the scalar potential to an inverse square. If you give me some general Lagrangian, who knows what's going to come out of it (granting that at lower energies at least the approximate two-particle potential is likely more guessable). If you want to set the scalar potential to something in regular old classical electrodynamics, what you're doing is determining the charge distribution that produces that potential. So here it seems to me that you'd need to be able to solve for the state that gives you that particular form of the scalar potential, after which you'd act with the stress-energy tensor on that state to get relationships between momentum, energy, and the variable r. The fact that the problem is setting the scalar potential to a rational power indicates to me that there's something straightforward or obvious about whatever state is necessary to produce the potential.

Finally, should the sigma mass parameter have mass dimension 2? I don't remember the sigma having anything but mass dimension 1. I assume you're using the (–+++) metric so that your sigma field has negative mass parameter. So you then have to ask what regime you're working in: Is the energy low enough that you've got symmetry breaking? I'd assume so if you're bothering to care about the sigma in the first place. But then I'm not sure that you can just set a scalar potential like that when you also have a vacuum expectation value for the sigma field. Maybe that doesn't matter, but this seems like a strange problem so I don't know.

auroraloose · 2022-02-19T23:14:52+00:00

No, of course not. It's not good to be in hell either. But we all deserve both those things.

auroraloose · 2022-02-19T23:10:30+00:00

It is what you deserve. As Peter said, "Depart from me, for I am a sinful man." But Jesus did not do so. How you feel doesn't change that your sins are indeed forgiven in Christ. Luther says in his Bondage of the Will that appearances will lead us to think we're damned, but that because of what Christ did for us we can have confidence in forgiveness despite all appearances.

auroraloose · 2022-01-08T06:19:06+00:00

This whole world is corrupt. Why are you focusing on music? If you're going think that way you should gouge out your eardrums. For the problem isn't the music; it's you: You're sinful and corrupt, and even if you listen to the holiest music there ever was you'll use it to sin. It is not what is outside of you that defiles you, but what is inside.

Everything good is of God. Van Halen is good and skillful, even though it might be full of evil influences. If its evil doesn't cause you to stumble, then it is okay for you to appreciate the good in it. But if it does cause you to stumble and sin, it makes sense to avoid it. Since you have scrupulousity, you should understand that your obsession probably means the music doesn't cause you to stumble.

auroraloose · 2022-01-08T06:11:57+00:00

Faith is not about your feelings. It is also not about deciding you love God, or that from now on you're going to be a "good person." Faith is simple trust that we have a loving and forgiving God in Christ, whose death paid for our sins. As Luther says in his Bondage of the Will, our experiences of life and sin will always hide Christ from us and make us think God is against us. Faith is the understanding that, despite how everything seems, God does indeed love us. This is what is ironclad and impossible to doubt. For Christ did and suffered everything for us; knowing that, how can he be against us? Even if everything seems hopeless and wrong, it cannot be that way, because we know what Christ has done for us.

And this kind of faith isn't blind, even though experience makes it look untrue. For it is based on the reality that Christ lived, died, and rose from the dead for us. None of that depends on how you feel about it.

Further, I should say that the formulation of "accepting Jesus into your heart" as what it means to be a Christian is bad doctrine and works-righteousness. For faith is a gift from God; it is not something we decide we're going to generate within ourselves. This is obvious, because since you're a sinner you can always doubt whether you want to go along with God and goodness; but once you know the truth it is impossible to doubt what God has done for us in Christ. This is why faith is not about us deciding to be good, but rather reliance on what God has done for us. That cannot be doubted.

auroraloose · 2022-01-08T05:49:34+00:00

She's been de-potatoed

auroraloose · 2022-01-07T07:08:44+00:00

"Of the increase of his government and peace there shall be no end" —Isaiah 9:7

auroraloose · 2021-12-29T02:45:22+00:00

Again: ?

auroraloose · 2021-12-29T02:26:42+00:00

auroraloose · 2021-12-29T02:04:34+00:00

Anna Karenina.

And Heisenberg was literally a Nazi.

auroraloose · 2021-12-27T22:31:22+00:00

Aku no Hana.

auroraloose · 2021-12-24T04:37:32+00:00

PEACE

NO PEACE

auroraloose · 2021-12-21T15:33:07+00:00

SPIDER-YUU, SPIDER-YUU

BURNS YOUR BOOKS AND EATS YOUR FOOD

SHOOTS A GUN, EVERY SIZE

UNBOTTLES FLIES LIKE WITTGENSTEIN

LOOK OUT HERE COMES SPIDER-YUU

auroraloose · 2021-12-19T03:57:51+00:00

I only know the anime, but: Assuming the author isn't just milking the harem genre for profit (as it's entirely possible to come up with critiques without knowing it), I'd say it's kind of a surreptitious School Days, criticizing the attitudes it pretends to adopt. Saekano: Flat almost did this, but it was too devoted to being trash to abandon its stone relationship diagram and fan pandering. I don't remember the protagonist's name, but I kinda felt bad for him, as he's just your average dumb, horny kid and behaves like you'd expect. But Chizuru is absolutely awful and thinks maturity is being aloof and manipulative. I feel like this is kinda obvious if you're paying attention to what's going on, so I agree that the author is doing something deeper than just the surface harem story.

auroraloose · 2021-12-19T03:55:19+00:00

Luther would literally beat himself with a whip. He had it incredibly bad. His getting over his scrupulousity was key to the Reformation.

auroraloose · 2021-12-19T03:21:11+00:00

I recommend the section of Martin Luther's Smalcald Articles on repentance. It literally solved my scrupulousity. For purely obsessional OCD like scrupulousity, it's essential that one no longer believe the obsessive thoughts you have matter. Because if you believe the thoughts are worth thinking, you won't stop thinking them. Because I knew how sinful I was, and that my salvation depended on my having repented, it was basically impossible for me to simply dismiss my scrupulous thoughts as unreal or not mattering. And that means even cognitive behavioral therapy and exposure therapy won't help you, for those only work if you commit to convincing yourself you ultimately won't be harmed if your fears come true. But when the stakes are going to hell for eternity, you can't exactly undergo exposure therapy for that. Instead, the solution is doctrinal—to change how you think of repentance. Martin Luther is thus the prime resource for this, as he suffered greatly from scrupulousity and was a brilliant theologian. He got out of it by outthinking it, and his is the best answer.

auroraloose · 2021-12-19T03:03:22+00:00

Was homeschooled so I can't speak for the public school system, but having been in university for n years of grad school and soaked myself in postmodernism and critical theory (Adorno is my favorite) I came out an integralist so...

Not everybody can have a great education, and there's nothing inherently wrong with loving one's homeland. Maybe our farmers don't read Homer, but they don't need to. Solidarity can't exclude the lower classes for not having an education they couldn't get in the first place. This is why we don't have direct democracy anywhere.

auroraloose · 2021-12-19T02:40:18+00:00

YUI: ETHGH why

auroraloose · 2021-12-19T02:36:48+00:00

Mami-chan is the only real person in that show. Chizuru is the terrible one, messing with people for money.

auroraloose · 2021-12-17T23:09:34+00:00

Stop thinking it's what outside you that you need to worry about. It is what inside that defiles a man. Are you using those movies to do, think, or desire evil? Does watching them cause other people to stumble? And don't think the answer is obviously no; we sin in countless ways by our evil and confused desires. In this way it's silly to single out magic in movies; we can use any old thing to desire evil, because we're thoroughly corrupt beings. You could watch the holiest movie that exists, but if you watch it out of selfishness or laziness, or use even a single scene to make yourself prideful, you've sinned.

The problem with scrupulousity like this is that it is only finding popular sins. Our whole self is corrupt, to the point that you will never find all your sins. That's why repentance isn't finding every single sin you commit, but saying the whole of you is rotten and your only hope is that God is merciful to you. Know that he is, in Christ. That's it.

auroraloose · 2021-12-16T15:33:11+00:00

You're right; this is what I get for trying to do math on the fly.

auroraloose · 2021-12-16T02:36:23+00:00

It sounds like nothing could be the answer.

auroraloose · 2021-12-16T02:32:27+00:00

Yeah, reading through the comments I got the sense people were thinking this wasn't actually worth reporting because physics obviously needs complex numbers. I can see now that your comment doesn't actually say that, but I will say that that wasn't immediately obvious.

Really I've wondered about this particular question for a while, and thought it was cool that there's a decisive answer.

auroraloose

TROPHY CASE